Hello,
I went through the LLVM build bots (and also the libc++ buildkites) and increased their ccache max size. There was a big impact on the flang builds on tcwg-jade-01 (which went from 1h–2h to 10min–30min), but not on other builds. One reason is probably that since I made this change earlier today, there wasn't time yet to finish enough several-hours-long builds to warm up the caches.
Since different machines have different disk sizes and free space I chose different ccache max sizes for them, as follows:
* tcwg-fx-02 hosts the following build bots: - clang-aarch64-sve-vls-2stage - clang-aarch64-sve-vls - clang-aarch64-sve-vla-2stage - clang-aarch64-sve-vla
All share the same ccache. I changed its max size to 20 GB. It's not a lot, but this machine is also used as a dev box so I though it would be good to preserve a fair amount of space.
* tcwg-jade-01 hosts the following build bots: - clang-armv8-lld-2stage - clang-armv7-vfpv3-2stage - clang-armv7-global-isel - clang-armv7-quick - clang-armv7-2stage - clang-armv7-lnt - flang-aarch64-latest-gcc - flang-aarch64-rel-assert - flang-aarch64-release - flang-aarch64-latest-clang - flang-aarch64-debug - flang-aarch64-out-of-tree - flang-aarch64-sharedlibs - flang-aarch64-dylib - clang-aarch64-full-2stage - clang-aarch64-global-isel - clang-aarch64-lld-2stage - clang-aarch64-quick
All armv7 and armv8 bots share one ccache, and all aarch64 bots share another. I changed the max size of each one to 100 GB.
* tcwg-jade-04 hosts the following build bots: - lldb-aarch64-ubuntu - lldb-arm-ubuntu - buildkite-linaro-armv8-libcxx-01 - buildkite-linaro-armv8-libcxx-02 - buildkite-linaro-armv8-libcxx-03 - buildkite-linaro-armv8-libcxx-04
The buildkite bots share a 50 GB ccache, while lldb-arm-ubuntu uses another 50 GB ccache due to being based on a different distro version. And lldb-aarch64-ubuntu also uses its own 50 GB ccache.
* tcwg-llvmbot_tk1-01.tcwglab hosts the following build bot: - silent-linaro-tk1-01
I changed the max cache size to 10 GB. There's not a lot of free space on the machine.
* tcwg-llvmbot_tk1-03.tcwglab hosts the following build bot: - normal-linaro-tk1-02
I changed the max cache size to 20 GB.
* tcwg-llvmbot_tk1-05.tcwglab hosts the following build bot: - silent-linaro-tk1-08
I changed the max cache size to 10 GB.
* The following tcwg-llvmbot_tk1-* machines are currently unreachable so I couldn't examine them: - tcwg-llvmbot_tk1-02.tcwglab - tcwg-llvmbot_tk1-04.tcwglab
* The following tcwg-llvmbot_tk1-* machines are running an llvmbot container but no builder container, so I didn't change their ccache configuration: - tcwg-llvmbot_tk1-06.tcwglab - tcwg-llvmbot_tk1-07.tcwglab - tcwg-llvmbot_tk1-08.tcwglab - tcwg-llvmbot_tk1-09.tcwglab
* tcwg-jade-02 is a GNU builder, and from peeking into a few containers running build jobs I have the impression that it doesn't use ccache. Should I look into it?
* Going through our ssh config file I didn't find these build bots that are listed at http://llvm.validation.linaro.org/ so I didn't check their ccache usage: - clang-arm64-windows-msvc-2stage - clang-arm64-windows-msvc - clang-arm64-windows-msvc-2stage - clang-arm64-windows-msvc - clang-native-arm-lnt-perf - clang-armv7-vfpv3-full-2stage - clang-thumbv7-full-2stage - libcxx aarch64 - libcxx aarch64 -fno-exceptions